Stepper



Jan; 5,1926.

R. VENZLAFF I STEPPER v original Filed Feb. 16,V 1921 sheets-sheet 1lll/illll/lllll Inymvez R. VENZLAFF STEPPER 2 Sheets-Sheet 2 OriginalFiled Feb. 16, 1921 [n we?? or Patented Jan. 5, 1926.

`UNITED STATES PATENT OFFICE.

RICHARD VENZLAFF, OF BERLIN, GERMANY, ASSIGOR OF TWO-THIRDS T0lAB/lI-IUR VON MUMM AND WALTER VON MUMM, BOTH OF BERLIN, GERMANY.

` STEPPER.

Original application tiled February 16, 1921. Serial No. 445,552.VInvii-Ierland this application led March 23, 1922, serial No. 546,175.

Toall whom t may concern.'

Be it known that I, RICHARD VENZLAFF, a citizen of Germany, residing atBerlin, Germany, have invented certain new .and useful Improvements inSteppers, of which the following is a specification. n

My invention relates to vehicles and more especially to vehicles glidingacross supports carried along by the vehicle itself. For the transportof loads across uneven roads or in regions lacking good roads, it hasalready been repeatedly proposed to employ in the place of vehiclesfitted with wheels and besides the class of vehicles commonly known astanks and operating by means of endless link-chains, vehicles moving onrunners which are 'alternately raised and then set down on the groundand acrossy which the vehicle then glides forward. As soon therefore asthe underframe along with the body has glided across a set of runners,in order to pass over on to another set which has ymeanwhile ybeen movedforward,- the first Set of runners is raised from the ground and shiftedforward along the underfraine only to be set down again on the ground infront of the un'derframe and once again to serve as a sup ort for theunderframe as it glides forwar f In vehicles of this particular kind itproved difficult to get along'with only two sets of runners, because theset temporarily raised from the ground could scarcely ever be loweredquick enough again and placed in front vof the underframe, to enablethis latter to move along uninterruptedly and without a hitch.

It is the object of my invention to provide a vehicle of the typespecified adapted to move along uninterruptedly on only two sets orpairs of runners.

In the drawings afIiXed to this specification and forming part thereof,a vehicle having only two sets of runners and embodying my invention isillustrated by way of eX- ample. In the drawinvs- Figs. 1 and 2 are aside elevation and end view, respectively, of the vehicle provided withmeans for raising and lowering the runners.

Fig. 3 is a part elevation of the rear-end vehic e sections on anenlarged scale,

Fig. 4 is a plan of the rear-end sections Renewed November 28, 1925.

of a ruimer, along Vwith the appropriate driving mechanism.

Fig. 5 isa cross section on line l-E in Fig. 3. f

Fig. 6 an elevation corresponding to that shown in Fig. 8, with theparts, however, shown in different working positions.

AReferring to the drawings, the frame is moved forward by the crankshaft causing it by means of connecting rods to glide ,on the rails 7 2across the rollers 73.

The

alternately displaced 180, the first and third and the second and fourthrunner cooperating with one another. On the crank shaft 77 turning fromthe right hand into the left hand' dead centre position (Fig. 6), theconnecting rod 79 pulls the feet 75 which are raised abo-ve the ground,forward across the rails 7 2 attached to the frame. As this takes placeduring the time in which the frame is also pushed across the rollers ofthefeet restiiiv on the ground, (each movement being e ected by one halfstroke of the crank), the runners will always be placed in time in frontof the frame whereby a continuous forward motion of the frame isproduced.

For the purpose of raising and lowering the runners, there are arrangedfor each ruimer on the crank shaft side by side two arms 8O and 8ldirected at right angles to one another, the one destined for drivingahead and the other for reverse. rIfhe two arms act alike though counterto one another, and according' to the direction in which the vehicle ispropelled, only one or the other arm will enter into operation. Each armoperates in one of two cam grooves V82. formed side by side in ahorizontal slide S3 moving by aid of slots 84 on studs projecting fromthe underframe. In an opening 86 formed at the upper end ion of theslide there engages a pivot 87 arranged at the end of a lever 88 mountedon an axle 89 located in bearings connected with the frame. Another axle90 extending in parallel thereto and carrying an arm 91, is coupled withthe axle 89 by a connecting rod 92. On each axle there is mounted a pairof arms 93 and 94, respectively, extending at right angles to the levers88 and 91 and serving to raise and lower, respectively,

two slotted slides 95 suspended from the arms 93 and 94, respectively,by links'96 and moving in vertical guides 97 arranged on the underframe.These slides 95 are provided with slots 98 on the lower edge of whichthe rollers 7 3 come to rest when the runner is raised. rIhe shape ofthe cam groove within which the arm 8O moves, is such that on theunderframe gliding forward with the rails 72 across the rollers 73belonging to the runners resting on the ground for the time being, theslide 83 will assume the position disclosed in Fig. 3. The rails 72having moved across the rollers 73, arm 80 forces the slide 83 to therear. By thisy means the lever 88 which engages the opening 86 of theslide, is rocked backward and slides 95 and the rollers 73 restingtherein as also the runners bearing the rollers are raised (Fig. 6),whereupon the crank draws the rollers forward in slot 98 and across therail. This having been effected, arm 80 causes the slide 83 to moveforward, whereby the lever arm 88 is caused U to rock forward and theslide 95 along with the runner suspended therefrom to be lowered, sothat the parts return into the position shown in Fig. 3.

During backward driving the arm 81 comes to operate in the. cam grooveappertaining to it and which is displaced 180o with regard to the othergroove, in the same manner as arm 80. In this case slide 83 is displacedin the counter direction for the purpose of raising' and lowering therunners.

In order to savepower, I have found it expedient to equalize the weightof the slides by counterweights acting on a rope 10() which engage it bysuitable means, and this in such a manner that the cam shaft whenelevating will not be required to perform any excessive work.

The front portion 210 of each runner can be arranged to turn about ahinge pin so as to assume an oblique position in case that an obstacleis encountered.

I wish it to be understood that I do not desire to be limit-ed to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

I claim:

1. A vehicle of the kind described comprising in combination two pairsof runners adapted to be alternately moved forward, a frame adapted toglide across said runners and a horizontal shaft extending across saidframe, horizontal slides with cam slots adapted to be displaced on saidframe, an arm on said shaft adapted to move within and in contact withsaid slot, slides connected with said runners and adapted to bedisplaced vertically on said frame for lifting said runners andconnecting rods establishing an operative connection between ,said shaftand said runners.

2. A vehicle of the kind 'described comprising in combination, two pairsof runners, adapted to be alternately moved in horizontal direction, aframe adapted to glide across said runners a horizontal crank shaftextending across said frame connecting rods for transmitting motion fromsaid crank shaft to said runners, horizontal slides with cam slotsadapted to be displaced on said frame, an arm on said shaft adapted tomove within and in contact with each slot, slides connected with saidrunners and adapted to be displaced vertically on said frame for liftingsaid runners, and means for counterbalancing said vertical slides.

In testimony whereof I aix my signature.

RICHARD VENZLAFF.

